This invention relates generally to robotic systems for displacing an end effector or tool through a prescribed path of motion for automated performance, for example, of manufacturing processes and the like. More specifically, this invention relates to an improved robotic system of modular construction and a related method of operation wherein an end effector position signal is coupled to multiple movable members and individually interpreted to derive individualized component movements.
A variety of robotic mechanisms are known in the art particularly for use in automated performance of various manufacturing processes and the like. Such robotic mechanisms typically comprise an assembly of mechanical components, some of which are configured to accommodate displacement along or about preselected axes. The assembled components commonly comprise a mechanical linkage which supports a so-called end effector or tool for displacement through a desired path of motion. Such robotic mechanisms have been constructed with relatively simple geometries having, for example, one or two degrees of mechanical freedom to permit end effector motion through relatively simple paths. More complex system assemblies have also been proposed with higher degrees of mechanical freedom, for example, five or six degrees of freedom, to permit end effector displacement through more complex paths as may be required in the performance of complex manufacturing operations. In any case, the assembled robotic linkage normally includes drive motors arranged along the length of the mechanical linkage for individual actuation, typically under computer control, to obtain the desired end effector path of motion as a function of time.
In the past, robotic systems have generally comprised customized mechanical assemblies and related customized control systems which have been designed to accommodate a specific operating environment. Computer control systems for the robotic mechanism have been programmed for transmitting individual joint position signals in parallel to the various movable joints of the robotic linkage, resulting in relatively complex and typically custom-tailored control programs in addition to relatively complex wiring arrangements which can interfere with the desired linkage displacements. Efforts to produce a robotic mechanism from modular components adapted for assembly in different configurations to accommodate different paths of motion have still required complicated programming systems and related complex wiring arrangements for coupling individualized actuation signals to each movable joint.
There exists, therefore, a significant need for an improved robotic system particularly of the type which can be assembled from modular components, wherein each movable joint of the assembled linkage is adapted for individualized response to a common command signal, thereby permitting a simplified programming system and corresponding simplifications in coupling the command signals to a plurality of movable joints. The present invention fulfills these needs and provides further related advantages.